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So how do you steal credential in memory in mobile?

It's not a technical question, it's a question when a few people argue (devil's advocate) that even if their app has an issue of storing the 'Login Credentials' in memory, what's the risk? Their arguments are:

  • They have jailbreak/ root detection implemented. So the app cannot be installed on a rooted device.
  • >>Counter argument: The JB/ root detection are completely by-passable as they are client side protections. Scenarios, a user can intentionally/ unintentionally bypass this check and install at his own device to enjoy banking and other apps also, which require a root. Second scenario, a security researcher can do the same thing to do a research and learn how this app works. If this app belongs to a reputed firm and he/ she makes this finding public, it would be reputation loss.
  • If you try to root the device which has the app already installed, the device will reboot and in this order kills the app's process and consequently clears the memory which holds the credentials.
  • >>Counter argument: There are a few malicious apps/ incidents we have come across where it's not really needed to reboot the device. The malwares/ exploits can take advantage of various CVEs to gain root access to the device which can be used to further dump/ read the memory.      Not possible? There are bunch of links on the internet which suggests it's possible- a few old, a few current. They range from malware to Remote access trojans. A few links:
  • https://blog.trendmicro.com/trendlabs-security-intelligence/new-androrat-exploits-dated-permanent-rooting-vulnerability-allows-privilege-escalation/ 
  • https://blog.trendmicro.com/trendlabs-security-intelligence/godless-mobile-malware-uses-multiple-exploits-root-devices/

The point here there could be N no. of possibilities to exploit something, if not today, maybe in near future. That does not mean, we'll not fix our problem and rather challenge others to prove that it's not possible. If that's the case, we need not develop secure applications just because there are so many perimeter defense available on the network? That's security through obscurity, which is bound to fail one fine day!

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